Purification, nanocrystallization and preliminary X-ray analysis of a C-terminal part of tropomodulin protein 1, isoform A, from Caenorhabditis elegans

The C-terminal part of tropomodulin protein 1, isoform A, from Caenorhabditis elegans was expressed in Escherichia coli and purified to homogeneity. Optimized from the initial nanoscreen, crystals grew to dimensions of 0.25 x 0.15 x 0.15 mm at 277 K using 28.0%(v/v) PEG 400 as the precipitant by the hanging-drop vapor-diffusion technique. A data set of 94.9% completeness was collected to a resolution of 1.98 Angstrom at 100 K using a synchrotron X-ray source (SER-CAT). The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a=31.7, b=50.6, c=107.1 Angstrom, and contained one molecule per asymmetric unit.